<!DOCTYPE html>

<iframe src="iframe.html"></iframe>
<script type="module">
  import * as Comlink from "https://unpkg.com/comlink@alpha/dist/esm/comlink.mjs";
  // import * as Comlink from "../../../../dist/esm/comlink.mjs";
  async function main() {
    const ifr = document.querySelector("iframe");
    await new Promise((resolve) => (ifr.onload = resolve));
    const f = Comlink.wrap(Comlink.windowEndpoint(ifr.contentWindow));
    alert(`1 + 3 = ${await f(1, 3)}`);
  }
  main();
</script>
